A battery charger normally employs a large, expensive, and heavy transformer for stepping down the AC line voltage to a value compatible with the battery voltage. This known charger can only recharge so called "rechargeable batteries, such as lead-acid batteries. So called transformer-less battery chargers are also well known in the art. These generally use a diode bridge circuit requiring at least four diodes and are also limited to charging (or recharging) of rechargeable batteries.
Throughout this specification, the term "desulphation" means the cleaning of the battery terminals.
The present invention includes a circuit capable of charging both rechargeable and non-rechargeable dry galvanic cells using a transformer-less circuit having a minimum number of components, thereby minimizing the cost and size of the apparatus. Further, the charging current is not influenced by the number of batteries being charged, but rather is determined by the accumulating capacity of the circuit.